<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        /*径向渐变,圆形渐变*/
      body{
         /* background-color: #21D4FD;*/
          background-image: linear-gradient(19deg, #21D4FD 0%, #B721FF 100%);
      }
    </style>
</head>
<body>

</body>
</html>